Industrial sewing machines often are used to attach one or more layers of material to a non-planar member. For example, a top layer, a layer of padding and backing layer may simultaneously be sewn onto a non-planar structure such as a portion of a chair or automobile seat. In many instances the non-planar base structure will include a plurality of intersecting surfaces which define at least a partial enclosure.
Sewing operations on non-planar structures, such as automobile seats, typically require a sewing machine with a pedestal extending from the sewing machine table directly beneath the needle. The pedestal includes the mechanical shuttle members which interact with the thread carried by the needle to create the stitches. Thus, in the prior art sewing machine, the non-planar structure can effectively be mounted upon the pedestal and moved relative thereto to carryout the necessary sewing operations. More particularly as the surface of the structure to be sewn is mounted on the pedestal of the prior art sewing machine, the various intersecting surfaces of the structure will extend downwardly from the pedestal toward the table of the sewing machine.
Although the above described prior art industrial sewing machine facilitates the sewing of fabrics and such onto non-planar articles, this prior art sewing machine does not facilitate the initial mounting of the non-planar structure onto the sewing machine or the removal of the structure therefrom. More particularly, the above described prior art industrial sewing machine operates in much the same manner as a standard sewing machine in that the needles are merely retracted slightly upwardly to place the article or structure to be sewn into its proper position with respect to the needle. Although this standard operation is quite acceptable for planar articles, this prior art construction makes the initial mounting and ultimate removal of a non-planar structure extremely difficult. Specifically, it is necessary for the operator of the above described industrial sewing machine to simultaneously advance and rotate the structure to be sewn through several planes. These complex movements to mount the structure to be sewn must be carried out very carefully because of the presence of the sewing machine needles. More particularly a sudden movement could injure the operator, damage the workpiece and/or break the needle. As a result of these constraints a large proportion of an operator's time with prior art sewing machines has been spent positioning the object to be sewn and then removing it from the machine.
In view of the above it is an object of the subject invention to provide a sewing machine that can more easily accept non-planar articles or structures to be sewn.
It is another object of the subject invention to provide a sewing machine that can reduce the time alloted to positioning an article or structure to be sewn.
It is a further object of the subject invention to provide an industrial sewing machine on which the space between the sewing machine arm and the portion of the table on which the workpiece is placed can be increased.
It is an additional object of the subject invention to provide a sewing machine wherein a portion of the table can be articulated away from the needles for mounting of an object to be sewn, yet wherein the sewing machine is extremely sturdy to enable precise sewing operations.